158 POLYGOXACE.K. 



petioled; flowering lirtinches in a rather strict panicle, leafless or with 

 a few little-reduced leaves at the base; whorls loose, not crowded, the 

 lower remote, pedicels slender, 1 to 2 times a.* long as the fruit, 

 tumidly jointed toward the base; inner fruiting sepals ovate-deltoid, 

 IJ to 3 lines long, with 3 to 5 thin triangular or subulate teeth on 

 each side; grain 1 only or with 2 other small ones. 



Introduced species in low lands, rarely collected, pci'haps mistaken 

 for R. conglomeratus. Lagunitas, Marin Co.; Presidio, San Fran- 

 cisco; and Alameda Co. July. -Sept. Inflorescence sometimes deep- 

 red. 



8. R. persicarioides L. Goldex Dock. Stems prostrate or 

 erect, seldom more than 1 ft. high, soft, mostly fistulou.s; herbage 

 yellowish-green, minutely pubescent; leaves oblong or lanceolate, 

 truncate or subcordate at base, acute at apex, a little undulate, the 

 blade 2 to 4 in. long, rather ehort-petioled; infloi-escence spicate- 

 conipacted with scattered sub-equal leaves, or the lower whorls remote; 

 pedicels capillary, veiy unequal, tumidly jointed at base; inner fruit- 

 ing sepals I to IJ lines long, acutely produced at apex, with 2 or ?, 

 awn-like teeth on each side; callous grains 8. 



Shores of lakes or in marshy lands. 3Iountain Lake, San Francisco; 

 Alvarado. July-Aug. 



7. POLYGONUM L. 

 Herbaceous or sufFrutescent plants. Leaves entire, alternate, with 

 scarious sheathing stipules ( ' ' sheaths "1, these entire, ciliate or lacerate. 

 Flowers white, red, or greenish, on jointed pedicels. Calyx red, 

 white, or sometimes greenish, in all ours 5-cleft or -parted, the divi- 

 sions erect in fruit. Stamens 4 to 9. .Styles 2 or 8. Achene lentic- 

 ular or triangular, enclosed in the fruiting calyx. Embryo curved, 

 lying in a groove at an angle of the endosperm. (Greek polus, many, 

 and gonu, knee, on account of the nodose zigzag stem of many 

 species.) 



Flowers in axillary clusters, eitlier widely separated or crnwded into a terminal 

 raceme, with foliHceous bracts; slaniens mostly H, the filaments or some of 

 them often dilated at base; achene triangnlar; leaves mohtly niirrow and 

 lanceolate or linear, jointed upon a very short petinle adnate to the short 

 sheath of the scarious siipules. — Subgenus Avicularia. 

 Perennial and more or le-s snfFnitescent. 

 Flowers several in a cluster, crowde'1 at the ends of the branclies; stipules 

 conspicuously lacerate: leives revolute; stems ascending or prostrate, 



from large woody I'ootstncks 1. P. Paronychia. 



Flo'.vers 1 or 2 in each axil, less crowded: stipules 2-lobed, the lower lobe 

 lacerate: leaves piane; fioweiing stems strictly erect Irom horizon al or 

 prostrate woody branches or from the woody crown of a very strong 



taproot -2. P. Bolanderi. 



Annuals. 



Prostrate; branches leafy to the enrls 8. P. avicularc. 



Erect; leaves diminishing upwards and becoming brac-lilce, the hranebea 



terminatiny in more or less loose spikes 4. P. ftpergnlariEefoi-Ttie. 



Flowers spicate, solitary in the axils, the internodes very sliort; stamiiis 8; 

 achene triangular; leaves very narrow, not jointed to the lacerate stipule; 

 ours slender wiry brittle annuals. — Subgenus Duravia. 



Plants .S to 7 in. high; flowers In terminal or axillary spikes 



5. P. Californicitm. 



